PT810917E - DEVICE FOR THE DISTRIBUTION OF FLUENT MATERIALS CONSTITUTED BY AT LEAST TWO COMPONENTS REAGING WITH OTHERS IN SPECIAL LEAKAGE RESINS - Google Patents

Description

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DEVICE FOR THE DISTRIBUTION OF FLUENT MATERIALS CONSISTING OF AT LEAST TWO COMPONENTS REAGING WITH OTHERS, ESPECIALLY LEAKING RESINS " The invention relates to a device for the delivery of flowable materials comprising at least two components which react with each other, in particular pouring resins, according to the preamble of claim 1.

There is known, for example from patent DE 34 20 222 A1, a device for filling at least one casting mold with flowing liquid media, in which the components of the casting mass are brought, by means of conveyor devices to at least one mixing device, from which the casting mass arrives at at least one casting mold. The conveyor device is formed by a piston-cylinder device, to which is associated a retraction cylinder for the backward movement of the conveyor piston of the piston and cylinder device. The known dosing system is, however, dimensioned such that the volume of the piston and cylinder device is sufficient to fill each casting mold, so that in the case of large molds, construction forms correspondingly result large expenses are required. The pressure gelatinising device can therefore be used in a limited manner, always having 1

always be put out of service always according to the corresponding needs. In this arrangement, a retraction device has to be associated with the conveying pistons, for the two components, the conveying pistons being connected together by a common connecting bridge, for purposes of synchronizing the strokes. The feed of the drive fluid to the conveyor pistons is made from containers with compressed fluid, the fluid from the two containers having the same pressure.

A device for metering and mixing of components is known from NL-A-77 02 748 in which the two piston-cylinder devices are actuatable via a common actuating bridge. A rigid mechanical coupling of the two piston and cylinder devices is therefore envisaged.

[0 0 04] In the case of the installation according to EP-A2-0 225 604, plunger and cylinder devices with pistons divided into two parts are used. These pistons divided into two parts are constituted by a conveying piston and a return piston between which a piston rod is arranged. Transmission of the force to the transport applied to the transport piston is effected by actuation on the rear face of the replacement piston with the compressed fluid.

The known installation of DE-A-42 08 769 also has an actuating bridge for actuating the conveyor and dosing pistons or, respectively, the piston and cylinder device. The metering pistons of the individual metering chambers are mechanically connected to each other by means of the actuating bridge and are driven by a common drive. 2

The object of the invention is to improve a device of the type mentioned in the introduction so that it can be used with standard dimensions and preferably with a good handling of the piston and cylinder devices for different volumes of the casting molds.

The problem is solved essentially by the features described in the characterizing part of claim 1.

The device according to the invention can be universally used for different volumes of the parts to be molded. In this case, there are, as a rule, a plurality of piston and cylinder device paths, depending on the volume of the workpiece to be molded. The lower limit of the displacement volume dimensioning of the piston and cylinder devices is then determined essentially by the viscosity of the components to be conveyed and the frequency of travel of the conveyor piston relative to the conveying speed. With increasing velocity, ie with viscous components, large cross-sections of passage for the piston and cylinder devices are required to ensure, in the time intervals predetermined by the frequency of rides, a filling of the spaces for the product, of the plunger and cylinder devices. Attention must be paid to the inlet cross-section when only the static inlet pressure of the supply vessel acts to fill the cylinder in the components. The frequency of rides that furthermore intervenes in the dimensioning of the displacement volume results from the quotient of the transport velocity by the volume of each ride. As opposed to the lower limit, essentially depending on the operation, according to the invention, the upper limit of the displacement volume is determined, either as a function of the precision of 3 | ~ L 's; the necessary dosing and the synchronous mode of operation of the two piston and cylinder devices, both the costs and the manageability of the system. This is because, with the increase in displacement or respectively the volume of the stroke of the piston and cylinder device, also the volume of the drive fluid increases correspondingly. In this way the overall system elasticity increases as a sum of the mechanical elasticity of the housing of the drive unit and of the piston and cylinder device, on the one hand, and of the elasticity of the fluids, thereby impairing the accuracy of the dosing. It should be noted here that the device for the transport pressure has to be sized to 100 bar, and more. as another criterion, the costs relating to expenditure on piston-cylinder devices or the overall system contribute to the upper limit of the displacement volume. Another criterion is the good handling of the various components, for example for maintenance and repair purposes.

In a first advantageous embodiment of the invention, it has been envisaged that the displacement volume of the piston and cylinder devices should be between 0.1 and 4 liters, preferably about 1 liter. It has been found that, with these sizing limits, a wider range of uses can be covered for the most diverse cast volumes, which may include essentially the above described criteria for viscosity, rpm, accuracy of dosing, costs, handling and speed of transport.

In addition, according to the invention there is provided a device for determining the position of the conveyor piston. This may be done, for example, by means of at least one increment indicator, a sensor, a limit switch or a similar sensor, associated with the drive device and / or the piston devices and cylinder.

In the context of the present invention, there is also integrated a locking member for the entry and / or the exit of the components, in the chamber of the conveyor, preferably in the bottom of the housing of each plunger and cylinder device which follows the the conveyor chamber. By this measure the inlet flow paths for the plunger and cylinder device or, respectively, for the mixing device can be minimized, which leads to correspondingly reduced flow resistances.

It is particularly advantageous in accordance with the invention that the conveyor piston and the retraction piston of the retraction device are kept at a certain distance from each other, leaving between the conveyor piston and the retraction piston, an intermediate wall which mutually separates a drive chamber facing the conveyor piston for the drive fluid and a chamber facing the replacement piston with a fluid for the return movement of the transport piston. Such piston and cylinder equipments with retraction device are also of simple handling, as standard components.

According to the invention, as a drive device, a piston and cylinder device can be associated with each piston and cylinder device, the cylinder chamber of which is connected to the drive chamber of the respective device of piston - cylinder. In this embodiment the relationships between the volumes of the components to be mixed can be previously and freely chosen by means of a drive unit control which also simultaneously takes care of the synchronous movement of the piston and cylinder device. Of course, a separate control can also be provided for synchronized movement of the piston and cylinder devices.

Alternatively, it is also possible for the drive device to have a piston and cylinder device with a stepped piston, the individual cylinder chambers of which are associated with a piston and cylinder device. In this case, the relatively low cost of construction of the drive device and the device for detecting the position of the conveyor piston (s) is advantageous, this device being preferably associated with the drive piston and cylinder device. In this embodiment of the drive device, the dosing ratio of the piston and cylinder devices is determined by the step of the drive piston, also providing synchronization of the conveyor cylinder of the piston and cylinder device.

From the foregoing, it is recommended according to the invention that a compensating valve device is provided between the cylinder chambers to detect the filling states of the piston and cylinder devices, provided for the transport of the components before starting the transport and being able to compensate or balance the amounts of fluid to be actuated in the drive system.

Of course, direct actuation on the transport pistons with compressed fluid can also be performed by the drive assembly. Therefore, it has however to be ensured that the compressed fluid is compatible with, or is adapted to the respective components. It is common to all the devices according to the invention that the piston-cylinder devices and the drive devices represent components groups separated from each other, so that it is possible to provide, for units of devices of equal piston and cylinder, different drive units. In this way, a modular system is provided in general, in which respective drive units can be selected according to the needs.

In the context of the invention there is also the fact that the actuating device is formed by means of the drive fluid through the piston of transport of the piston and cylinder device during the gelling phase to maintain a post- tightening pressure, in the casting mold (s), so that no other devices are required for the production of such postpressure.

According to another idea of the invention, the piston for conveying a piston and cylinder device can be formed as a plunger pump, the separation between the product chamber and the drive chamber being made by a seal, preferably fixed in the cylinder chamber.

In certain circumstances it may be recommended in accordance with the invention to provide for the feeding of each of the components, from the supply vessel to the piston and cylinder device, a loading pump or a pumping device similar. Such a support for the transport of the components may for example be made by an appropriate configuration within the supply vessel, for example by means of a screw conveyor, placed in the supply vessel, or the like. Also within the scope of the invention is the fact that the filling device is formed of at least two resin casting molds with a mixing device associated with each casting mold, of the mixing devices connected by means of feed pipes which can be locked with the piston and cylinder devices. In this way, several casting molds can be filled in a time-shifted manner.

According to one embodiment, at least one buffering device may be associated with each of the casting molds formed to maintain the post-clamping pressure in the casting mold during the gelling step. A buffer device of this type is described, for example, in DE 27 48 982 C 2.

It is therefore particularly advantageous if the buffer device is placed before the respective mixing device, respectively with a buffer element for each component. It is thus possible to conduct the components separated from one another in a composition having the desired ratio, by means of the buffer element, to the associated mixing device.

Furthermore, according to the invention, it has been provided that the buffer device is formed as a plunger and cylinder device with a stepped plunger for the at least two components, so as to obtain a particularly compact and simple construction.

Finally, according to the invention, it has been envisaged, in a special embodiment of the invention, that the plunger and cylinder devices, and optionally with the drive device, are formed as an at least double, to the mixing device, 8 Γ

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the two units, in contrast, transporting the respective components to the mixing device. Due to this mode of operation of the piston and cylinder devices, in opposing rides, a continuous feeding of the components to the mixing device is carried out, so that the casting mold can be filled without interruptions, even in several walks. The duplication of the constructional units does not necessarily have the consequence of also requiring two drive groups for the drive device. For example, a drive group, for example a hydraulic group, may be sufficient to act on the drive units, which, in turn, act on the transport plungers of the plunger and cylinder devices.

Other objects, advantages, features and possibilities of use of the present invention result from the following description of embodiments, in connection with the accompanying drawings. Thus, all features described and / or represented graphically, by themselves or in any convenient combinations, constitute the object of the present invention, also regardless of the summary thereof in the claims or references thereof.

The figures of the drawings depict: Fig. 1 is a schematic representation of a device for dispensing resin for pouring; FIG. 2, another embodiment of a device according to the invention; FIG. 3, another embodiment of a device according to the invention; Fig. 4, a fourth embodiment of a device according to the invention; FIG. 5 shows the representation of a piston and cylinder device for conveying a component according to FIGS. 1 to 4, but with an additional locking member at the bottom of the cylinder; FIG. 6 is a representation of a plunger and cylinder device with plunger for conveying a component; FIG. 7, a device according to the invention, analogous to FIG. 5, but for a multiple molded part; and Fig. 8, a buffer element for a gelling pressure device according to fig. 7.

The dosing device according to fig. 1 has two supply vessels (1,2) for the components of the casting mass or, respectively, the casting resin.

The supply containers (1,2) can be kept under vacuum, which is not necessary in all cases, however. From the supply containers (1,2), the components are preferably provided with locking valves (3) or (4), respectively, for the product chamber (5,6) of the supply devices piston and cylinder (7, 8). The piston and cylinder devices (7, 8) furthermore have a chamber (9) or (10), respectively, for the drive fluid, these chambers (9) and (10) being connected via (11,12) respectively to a chamber (13, 14) of the actuating piston of a piston and cylinder device 10

(60,61). The piston and cylinder devices (7, 8) each have a conveying piston (17, 19) and, at a certain distance therefrom, pistons (18, 20) associated with piston rods , 23). In an extension of the piston rods (22, 23) there are incremental indicators (24, 25) for evaluating the path of the piston and cylinder device (7, 8). In the replacement chambers 26,27, separated by a partition wall 28,29 from the drive fluid chamber 9,10, a compressed fluid can be introduced through a connection 30,31, , for example compressed air, for the replacement movement of the pistons 19, 20 and 17, 18. In addition, a vent (32, 33) is provided on the rear face of the replacement pistons (18, 20) on the cylinders.

The conduits 34,35 of the components exiting the product chamber 5,6 lead to a mixing device 836) and can be blocked by valves 37,38.

The operation of the device according to the invention is as follows: By inserting replacement product through the connections 30,31, the pistons 17, 18 and 19, (3,4) are open and the valves (37, 38) are facades. In this way, the components flow from the supply containers (1,2) to the corresponding product chambers (5,6). In the movement of retracted pistons 17,18 and 19,20 the drive fluid travels to the drive chamber 9,10 so that through the connecting conduits 11,12, flows into the cylinder chamber (13, 14) of the drive piston device and the cylinder (60, 61), the fluid on the rear side of the drive piston (15, 16) going through the conduits (39, 40) and the valves (41, 42) for the drive unit (43) for the drive fluid.

In the next step, the valves (3,4) are closed and the valves (37,38) are opened for the mixing device (36). Then the drive pistons 15,16 are actuated with the compressed fluid from the group 43 so that the drive fluid in the piston chamber 13,14 goes to the drive chamber 9 , 10) of the piston and cylinder device (7, 8), their piston devices (18, 17) or respectively (20, 19) performing a ride, so that the components arrive, in a synchronized manner and with the desired volume ratio, to the mixing device 36, mixing therein with one another.

In order to synchronize the movements of the sidewalks, a control and control unit (not shown) is provided which, by means of the incremental indicators (24,25), through the valves (41,42), controls synchronized way, controlling the desired relationships between tours. The described device allows a free preselection of the respectively sent volumetric ratios and the conveyor speeds of the components, enabling, for certain ranges of viscosity of the components and suitably adapted nominal widths of the feed conduits and / or valves, without loading pumps components. The device is universally applicable to the volumes of the parts to be molded. The drive piston and cylinder devices 60,61 and the piston devices of the product and cylinder 7,8 are separated as construction groups so that it is possible to provide different drive units 60,61 for units (7,8) equals. A modular system is thus provided globally. This makes it possible to simply adapt the device for distributing the components under various conditions.

The device according to fig. 1 can work on rides or courses, so that the material mixed in rides, is made available to the various casting molds. But a continuous feeding of the casting mold could also be envisaged and is provided in the construction unit according to Fig. 1, a second unit, working in opposition to the first one, driving the respective components to the mixing device 36, as shown in Fig. 2. A continuous filling service is thus possible without interruption of the pouring jet. In the case of the embodiment according to FIG. 2, the various parts corresponding to those of fig. 1 have the same reference numerals. The drive units in the device according to fig. 2, have the reference 43 ', to indicate that variants of the drive according to the embodiments shown in Figs. 1, 3 and 4. While units with plunger and cylinder and drive units are duplicated, it is recommended, for reasons of ease of construction, to form the two components supply vessels in only one type.

The advantage of the device described in the form of a modular construction with exchange of drive piston and cylinder devices can be seen from Fig. 3. The device according to fig. 3 differs from that shown in FIG. 1 in that a stepped piston and cylinder device (44), the cylinder chambers (13, 14) of which are connected to the drive chambers (9, 10) of the piston and cylinder devices ( 7,8). In this way the dosing ratio is determined unequivocally and the synchronization of the two piston and cylinder devices (7, 8) is provided. Further, in Fig. 3 shows the possibility of conveying a component from a supply vessel (1,2), by means of a loading pump (45), to the product chamber, in the present case the product chamber (6) of the piston and cylinder device (8). The intercalation of an additional charge pump is considered in particular by the viscosities of the various components. Of course, a loading pump may also be associated with each piston and cylinder device.

In the case of the cylindrical stepped plunger device 44, the two cylinder chambers 13,14 are separated from one another by a partition wall 46, it being advantageous that the seals are not in contact with the two sides, with abrasive material, or that react with each other.

The embodiment of the drive unit according to FIG. 3 is chosen in particular when it is fixed the mixing ratio of the components, or e / a is not changed over a long time. It is then also possible to change the

piston to modify the mixing ratio. The described installation is less expensive than that described in fig. 1, with regard to the technical means of control.

A compensating valve device (63) was provided between the cylinder chambers (13, 14) to detect the filling states of the various plunger and cylinder devices, prior to the commencement of transport and compensating or respectively , adjusting the amounts of actuating fluid of the drive system.

In Fig. 4, another embodiment of the base system of FIGS. 1 to 3. In this case, the drive unit 43 is formed as a group of compressed fluid, providing a direct connection to the drive chambers 9,10 of the piston and cylinder devices (7,8). Together with the variant embodiment according to fig. 1, the mixing ratio of the components can also be adjusted freely here. Incidentally, in this variant, care must be taken that the compressed product supplied from the group of compressed medium 43, is chemically bearable. For the synchronized movement of the piston-cylinder device (7, 8), the supply pipes of the compressed fluid of the control or regulating valves (64, 65) are used.

In Fig. 5 shows a piston and cylinder device for conveying a casting resin component, the locking member (3,4) for the inlet of the components being integrated in the bottom of the housing (62) which follows the transport chamber (5) or (6). By this measure, the inlets of the supply containers (1,2) for the piston and cylinder devices (7, 8) can be minimized. In the preferred embodiments, the locking member (3,4) can be actuated with a pneumatic or hydraulic cylinder (63).

Instead of the plunger and cylinder devices (7, 8) indicated in Figs. 1 to 4, it is of course also possible to use a plunger and cylinder device with a plunger according to FIG. 6. In this case, in analogy with the exemplary embodiment according to Fig. 1, the product chamber is designated by 5 the drive chamber and by the piston replacement chamber 6, while the transport piston is indicated by 17 ' respectively, (19 '). The replacement piston is again designated by reference (18,20). The separation between the product chamber (5) and the drive chamber (9) is done through a cylinder seal (47). which is attached to the camera

Of course, also the material of the plunger and cylinder devices may be any, for example a ceramic, in particular a ceramic of oxides, may be used.

It is also understood that, instead of mechanical actuations by fluids, they can be used, for example threaded-axis drives, for movement of the drive pistons (15, 16 or, respectively, 44).

It is also possible in the same way for the device according to the invention to be used not only for two but also for more components of the casting mass, the supply vessels, feed conduit, piston and cylinder and the drive unit, for example in the form of triple-stage pistons. The device can also operate reproducibly in programmable courses. In addition, it is possible to use the devices according to fig. 1 to 4, simultaneously, as pressure retention devices, when gelling under pressure, for maintaining the post-clamping pressure. The device according to the invention may be considered not only for the pressure gelling process but also for all other pouring uses.

Inasmuch as incremental indicators are required, it is of course possible to provide them with piston and cylinder devices on the side of the product (7, 8) and / or on the piston and cylinder devices on the drive side ( 60.61 or, respectively, 64). Preferably they are placed in the piston and cylinder devices on the side 16 Γ L ·, of the product (7,8), as this results in a greater precision of the measurements.

A further advantage of the device according to the invention is that, in comparison with the conveyor pumps, substantially higher pressures can be obtained, so that with both the individual components and also with the casting mass, longer distances can be overcome with smaller cross-sections.

[0048] Fig. 7 shows a variant of the systems previously described, in particular that of Fig. 3. In order to enable a better use of the dosing plant, a through-mixer (53) is associated with each pouring mold (52) with a buffer device (54). They may thereby fill several leak molds 52, out of time, and maintain the post-pressure by means of the respective buffer device 54 during the gelling step. A possible embodiment of the buffer device 54 associated with the passage mixers 53 is shown for example in Fig. 8, in which the components are conducted separately from each other and brought back to the desired proportions for the formulation. The buffer device 54 may be constructed in a manner analogous to the plunger and cylinder device 44 according to FIG. 3 with a stepped piston 55 and a working fluid received in a pressure vessel 56.

The supply of the various components to the buffer device 54 is via feed conduits 57,58, and the locking valves 59 are connected in the conduits connecting the buffer devices 54, respectively. so that during the gelling phase the buffers 54, with the through-mixer 53 and the casting die 52 are disengaged from the rest of the system. A multi-use of the dosing system is thus possible.

Lisbon, June 29, 2001

0 OFFICIAL AGENT OF INDUSTRIAL PROPERTY 18

Claims (16)

Apparatus for the distribution of flowable materials, comprising at least two components which react with one another, in particular pouring resins, the components being conveyed from filling containers (1,2) to delivery devices piston and cylinder (1,2) associated therewith (7,8) and provided thereto to a mixing device (36), retracting devices (18,20) for the conveying pistons (17, 19) and actuating devices ( 60,61) to act on the conveying pistons (17, 19) with a fluid under pressure, and the active surfaces of the pistons on the side of the conveyor and the drive side of the piston and cylinder devices (7,8) (18, 20), in that, in order to synchronize the movement of the journals of the conveying pistons (17, 19), there is provided, for each of the piston and cylinder devices (7, 8) a unit of and control for the dosed feed of the drive fluid to the conveying pistons (17, 19) and a balancing valve device which detects, prior to commencement of transport, the filling states of the piston and cylinder devices, respectively, determines the quantities of fluid of the drive system to be applied. Device according to claim 1, characterized in that the displacement volume of the piston and cylinder devices (7,8) is, for each, between 0.1 and 4 liters, preferably about 1 liter. 1 Device according to any of the preceding claims, characterized in that at least one device (24,25) is provided for detecting the position of the conveying piston (s) (17, 19). Device according to any one of the preceding claims, characterized in that a locking member (3,4) is provided for the entry and / or exit of the components in the conveyor chamber, preferably in the bottom (62) of the housing, which follows the conveyor chamber, of the respective piston and cylinder device (7,8). Device according to any one of the preceding claims, characterized in that the conveying piston (17.19) of the piston-cylinder device (7,8) and the retraction piston (18,20) of the replacement device are mounted on a piston rod (22, 23) at a distance from one another and a partition wall (28, 29) between the conveyor piston (17, 19) and the retraction piston (18, 20), which separates from each other a a drive chamber (9, 10) for the drive fluid facing the conveyor piston (17, 19) and a chamber (26) facing the retraction piston (18, 20) for actuation with a backward movement fluid of the conveying piston (17, 19). Device according to any one of the preceding claims, characterized in that a piston-cylinder piston device (60,61) is associated with each piston-cylinder device (7,8), the cylinder chamber (13, 14) is connected to the actuating chamber (9, 10) of the respective piston and cylinder device (7,8) (fig). 2 L-1 Device according to one of Claims 1 to 5, characterized in that the drive device comprises a piston-operated piston device (44) with a stepped piston, the individual cylinder chambers (13, 14) of which are respectively associated a drive chamber (9, 10) of a piston and cylinder device (7, 8) (Figure 3). Device according to one or more of claims 1 to 5, characterized in that the actuating device, with control and / or control valve interlocking (64, 65), is formed for direct actuation of the conveying pistons (17 , 19) with the fluid under pressure (Figure 4). Device according to any one of the preceding claims, characterized in that the drive device is formed by means of the drive fluid through the conveying pistons (17, 19) of the piston and cylinder devices (7, 8), maintain , during the gelling step, a complementary tightening pressure in the at least one casting mold (52). Device according to any one of the preceding claims, characterized in that the conveying piston of each of the piston and cylinder devices is formed as a plunger (17 ', 19'), the separation between the chamber for the product (5 ) for the reception of each component, and the actuating chamber (9) for actuation with the actuating fluid, made by means of a seal (37) which is preferably fixed in the cylinder chamber (Figure 6) . Device according to any of the preceding claims, characterized in that it is provided for 3 Γ u supplying the respective components of the supply containers (1,2) to the piston and cylinder device (7, 8), a loading pump or similar pumping device (45). Device according to any one of the preceding claims, characterized in that, for filling of at least two casting molds (52) with casting resin, a mixing device (53) is associated with each casting mold (852) , each of the mixing devices (53) being connected by means of supply conduits (57,58) which can be locked with the piston and cylinder devices (7, 8) (Figure 7). Device according to claim 12, characterized in that each of the casting molds (52) is associated with at least one capping device (54), which is formed so as to maintain the post-pressure of in each of the casting molds (52). Device according to claim 13, characterized in that the buffer device (54) is arranged upstream of the respective mixing device (52), respectively, with a buffer element for each component. A device according to any one of claims 13 or 14, characterized in that the buffer device (54) is formed as a piston and cylinder device with a stepped piston (55) for the at least two components (Figure 8). 4 Device according to any one of the preceding claims, characterized in that the piston and cylinder devices (7,8), possibly with drive means (431) are formed as a double construction unit, relative to the mixing device (36), providing the two construction units and their respective components, in phase opposition, to the mixing device 36 (Figure 2). Lisbon, June 29, 2001 THE OFFICIAL AGENT OF INDUSTRIAL PROPERTY 5